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    <title>Document</title>
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    <ul class="level-1">
      <li class="item-i">I</li>
      <li class="item-ii">
        II
        <ul class="level-2">
          <li class="item-a">A</li>
          <li class="item-b">
            B
            <ul class="level-3">
              <li class="item-1">1</li>
              <li class="item-2">2</li>
              <li class="item-3">3</li>
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          <li class="item-c">C</li>
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      <li class="item-iii">III</li>
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